This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The overall goal of this study is understand the role of lytic viral replication during acute EBV infection of immunocompetent and immunosuppressed hosts. The proposal includes the following specific aims: Specific Aim #1 - What is the role of viral replication in primary rhLCV infection after oral inoculation of immunocompetent rhesus macaques? Specific Aim #2 - What is the role of viral replication in primary rhLCV infection after oral inoculation of SHIV immunosuppressed rhesus macaques? Specific aim #3 - How early do CD8+ CTL specific for lytic proteins develop in acute rhLCV infection? These studies will elucidate the role of lytic viral replication and the immune response during acute infection that would otherwise be difficult, or impossible, to study in humans. A better understanding of the interplay between lytic EBV infection and the immune response to lytic EBV proteins will contribute to development of novel therapeutic approaches for control of EBV infection and diseases associated with lytic EBV replication, such as oral hairy leukoplakia.